It is not entirely beyond him for this time next year for Holmes to be on an NFL roster. But it will be incredibly tough for him and he has to start right now, which he seems to have done.

But he basically has to NOT do what Hayne did.

He could have learnt under one of the best minds in the game with Pete Carroll who actually needed a Punt Returner at the time and instead went to the 49ers who were pulling the team apart and rebuilding, because of something stupid like he wouldn't be getting paid until he made the 53 man roster.
They also bought in a coach from Europe because it was clear they didn't give a crap about their season and it was probably above his head to be coaching an NFL team. He probably thought going to a crap team meant it would be easier to hold a roster spot because there'd be no competition, whoops.
But it's not about the money for Hayne, hah.

Anyway back to Holmes...for his weight/height there are a few positions which he could try out for but similar to Hayne his best bet would be a hybrid special teams guy working his way up. Ignoring anything written by our media because they have no clue by the sounds of it but the speed means nothing if you can't create separation which is tested by the cones, short shuttle drills at the combine.
The IMG academy where that Jordan kid who played for the Souths got drafted by the Eagles would be a good start to learn everything he needs to know and more. From there and going to participating in the combine will probably be the longest and hardest part in the journey.
But the biggest benefit to the draft is if he works his butt off to be drafted even if its in the late rounds which it probably will be, and then he works his butt off even more to make the 53 man roster he will earn a contract for four years like all draftees too. It'll probably be 500-900k going up each year but the biggest benefit is getting that contract. That's also guaranteed money on top of whatever other bonuses they get.

If he half arses it like Hayne did he will probably not make it. But if he tries to at least do the above, get drafted and make a roster there'll be more growing room he'll give himself a better shot at lasting in the NFL.
I hope he gets advised well and makes the right decisions to give himself the best possible chance.

The Warriors have made themselves look quite stupid in this instance. Firstly by releasing Lino to us (thank you very much) and then basically told Johnson he wasn’t going to get an offer beyond 2019 only to come out and say “we don’t want a player who doesn’t want to be here.” Like no wonder he doesn’t...

Wow every year releases and player swapping clubs gets worse and worse. It really turns fans off the game, knights seemed to have got it right this time for once. I just cant see how players and coaches can play for a team knowing they be somewhere else the following year. Guess its just money that talks now